embark-area-51/lib/modules/blockchain_connector/index.js

632 lines
18 KiB
JavaScript

const Web3 = require('web3');
const async = require('async');
const Provider = require('./provider.js');
const utils = require('../../utils/utils');
const WEB3_READY = 'blockchain:ready';
// TODO: consider another name, this is the blockchain connector
class BlockchainConnector {
constructor(embark, options) {
const self = this;
this.plugins = options.plugins;
this.logger = embark.logger;
this.events = embark.events;
this.config = embark.config;
this.web3 = options.web3;
this.isDev = options.isDev;
this.web3Endpoint = '';
this.isWeb3Ready = false;
this.wait = options.wait;
self.events.setCommandHandler("blockchain:web3:isReady", (cb) => {
cb(self.isWeb3Ready);
});
self.events.setCommandHandler("blockchain:object", (cb) => {
cb(self);
});
if (!this.web3) {
this.initWeb3();
} else {
this.isWeb3Ready = true;
}
this.registerServiceCheck();
this.registerRequests();
this.registerAPIRequests();
this.registerWeb3Object();
this.registerEvents();
}
initWeb3(cb) {
if (!cb) {
cb = function(){};
}
if (this.isWeb3Ready) {
this.events.emit(WEB3_READY);
return cb();
}
const self = this;
this.web3 = new Web3();
if (self.wait) {
self.wait = false;
return cb();
}
let {type, host, port, accounts, protocol, coverage} = this.config.contractsConfig.deployment;
if (!BlockchainConnector.ACCEPTED_TYPES.includes(type)) {
this.logger.error(__("contracts config error: unknown deployment type %s", type));
this.logger.error(__("Accepted types are: %s", BlockchainConnector.ACCEPTED_TYPES.join(', ')));
}
if (type === 'vm') {
const sim = self._getSimulator();
self.provider = sim.provider(self.config.contractsConfig.deployment);
if (coverage) {
// Here we patch the sendAsync method on the provider. The goal behind this is to force pure/constant/view calls to become
// transactions, so that we can pull in execution traces and account for those executions in code coverage.
//
// Instead of a simple call, here's what happens:
//
// 1) A transaction is sent with the same payload, and a pre-defined gas price;
// 2) We wait for the transaction to be mined by asking for the receipt;
// 3) Once we get the receipt back, we dispatch the real call and pass the original callback;
//
// This will still allow tests to get the return value from the call and run contracts unmodified.
self.provider.realSendAsync = self.provider.sendAsync.bind(self.provider);
self.provider.sendAsync = function(payload, cb) {
if(payload.method !== 'eth_call') {
return self.provider.realSendAsync(payload, cb);
}
self.events.request('reporter:toggleGasListener');
let newParams = Object.assign({}, payload.params[0], {gasPrice: '0x77359400'});
let newPayload = {
id: payload.id + 1,
method: 'eth_sendTransaction',
params: [newParams],
jsonrpc: payload.jsonrpc
};
self.provider.realSendAsync(newPayload, (_err, response) => {
let txHash = response.result;
self.web3.eth.getTransactionReceipt(txHash, (_err, _res) => {
self.events.request('reporter:toggleGasListener');
self.provider.realSendAsync(payload, cb);
});
});
};
}
self.web3.setProvider(self.provider);
self._emitWeb3Ready();
return cb();
}
protocol = (type === "rpc") ? protocol : 'ws';
this.web3Endpoint = utils.buildUrl(protocol, host, port);
const providerOptions = {
web3: this.web3,
accountsConfig: accounts,
blockchainConfig: this.config.blockchainConfig,
logger: this.logger,
isDev: this.isDev,
type: type,
web3Endpoint: self.web3Endpoint
};
this.provider = new Provider(providerOptions);
self.events.request("processes:launch", "blockchain", () => {
self.provider.startWeb3Provider(() => {
this.getNetworkId()
.then(id => {
let networkId = self.config.blockchainConfig.networkId;
if (!networkId && constants.blockchain.networkIds[self.config.blockchainConfig.networkType]) {
networkId = constants.blockchain.networkIds[self.config.blockchainConfig.networkType];
}
if (networkId && id.toString() !== networkId.toString()) {
self.logger.warn(__('Connected to a blockchain node on network {{realId}} while your config specifies {{configId}}', {realId: id, configId: networkId}));
self.logger.warn(__('Make sure you started the right blockchain node'));
}
})
.catch(console.error);
self.provider.fundAccounts(() => {
self.isWeb3Ready = true;
self.events.emit(WEB3_READY);
self.registerWeb3Object();
self.subscribeToNewBlockHeaders();
});
});
});
}
_emitWeb3Ready() {
this.isWeb3Ready = true;
this.events.emit(WEB3_READY);
this.registerWeb3Object();
this.subscribeToPendingTransactions();
}
_getSimulator() {
try {
return require('ganache-cli');
} catch (e) {
const moreInfo = 'For more information see https://github.com/trufflesuite/ganache-cli';
if (e.code === 'MODULE_NOT_FOUND') {
this.logger.error(__('Simulator not found; Please install it with "%s"', 'npm install ganache-cli --save'));
this.logger.error(moreInfo);
throw e;
}
this.logger.error("==============");
this.logger.error(__("Tried to load Ganache CLI (testrpc), but an error occurred. This is a problem with Ganache CLI"));
this.logger.error(moreInfo);
this.logger.error("==============");
throw e;
}
}
registerEvents() {
const self = this;
self.events.on('check:wentOffline:Ethereum', () => {
self.logger.warn('Ethereum went offline: stopping web3 provider...');
self.provider.stop();
// once the node goes back online, we can restart the provider
self.events.once('check:backOnline:Ethereum', () => {
self.logger.warn('Ethereum back online: starting web3 provider...');
self.provider.startWeb3Provider(() => {
self.logger.warn('web3 provider restarted after ethereum node came back online');
});
});
});
}
onReady(callback) {
if (this.isWeb3Ready) {
return callback();
}
this.events.once(WEB3_READY, () => {
callback();
});
}
registerServiceCheck() {
const self = this;
const NO_NODE = 'noNode';
this.events.request("services:register", 'Ethereum', function (cb) {
async.waterfall([
function checkNodeConnection(next) {
if (!self.provider || !self.provider.connected()) {
return next(NO_NODE, {name: "No Blockchain node found", status: 'off'});
}
next();
},
function checkVersion(next) {
// TODO: web3_clientVersion method is currently not implemented in web3.js 1.0
self.web3._requestManager.send({method: 'web3_clientVersion', params: []}, (err, version) => {
if (err) {
self.isWeb3Ready = false;
return next(null, {name: "Ethereum node not found", status: 'off'});
}
if (version.indexOf("/") < 0) {
self.events.emit(WEB3_READY);
self.isWeb3Ready = true;
return next(null, {name: version, status: 'on'});
}
let nodeName = version.split("/")[0];
let versionNumber = version.split("/")[1].split("-")[0];
let name = nodeName + " " + versionNumber + " (Ethereum)";
self.events.emit(WEB3_READY);
self.isWeb3Ready = true;
return next(null, {name: name, status: 'on'});
});
}
], (err, statusObj) => {
if (err && err !== NO_NODE) {
return cb(err);
}
cb(statusObj);
});
}, 5000, 'off');
}
registerRequests() {
const self = this;
this.events.setCommandHandler("blockchain:reset", function(cb) {
self.isWeb3Ready = false;
self.initWeb3(cb);
});
this.events.setCommandHandler("blockchain:get", function(cb) {
cb(self.web3);
});
this.events.setCommandHandler("blockchain:defaultAccount:get", function(cb) {
cb(self.defaultAccount());
});
this.events.setCommandHandler("blockchain:defaultAccount:set", function(account, cb) {
self.setDefaultAccount(account);
cb();
});
this.events.setCommandHandler("blockchain:getAccounts", function(cb) {
self.getAccounts(cb);
});
this.events.setCommandHandler("blockchain:getBalance", function(address, cb) {
self.getBalance(address, cb);
});
this.events.setCommandHandler("blockchain:block:byNumber", function(blockNumber, cb) {
self.getBlock(blockNumber, cb);
});
this.events.setCommandHandler("blockchain:gasPrice", function(cb) {
self.getGasPrice(cb);
});
this.events.setCommandHandler("blockchain:networkId", function(cb) {
self.getNetworkId().then(cb);
});
this.events.setCommandHandler("blockchain:contract:create", function(params, cb) {
cb(self.ContractObject(params));
});
}
registerAPIRequests() {
const self = this;
let plugin = self.plugins.createPlugin('blockchain', {});
plugin.registerAPICall(
'get',
'/embark-api/blockchain/accounts',
(req, res) => {
self.getAccountsWithTransactionCount(res.send.bind(res));
}
);
plugin.registerAPICall(
'get',
'/embark-api/blockchain/accounts/:address',
(req, res) => {
self.getAccount(req.params.address, res.send.bind(res));
}
);
plugin.registerAPICall(
'get',
'/embark-api/blockchain/blocks',
(req, res) => {
let from = parseInt(req.query.from, 10);
let limit = req.query.limit || 10;
self.getBlocks(from, limit, false, res.send.bind(res));
}
);
plugin.registerAPICall(
'get',
'/embark-api/blockchain/blocks/:blockNumber',
(req, res) => {
self.getBlock(req.params.blockNumber, (err, block) => {
if(err){
self.logger.error(err);
}
res.send(block);
});
}
);
plugin.registerAPICall(
'get',
'/embark-api/blockchain/transactions',
(req, res) => {
let blockFrom = parseInt(req.query.blockFrom, 10);
let blockLimit = req.query.blockLimit || 10;
self.getTransactions(blockFrom, blockLimit, res.send.bind(res));
}
);
plugin.registerAPICall(
'get',
'/embark-api/blockchain/transactions/:hash',
(req, res) => {
self.getTransaction(req.params.hash, (err, transaction) => {
if(err){
self.logger.error(err);
}
res.send(transaction);
});
}
);
plugin.registerAPICall(
'ws',
'/embark-api/blockchain/blockHeader',
(ws) => {
self.events.on('blockchain:newBlockHeaders', (block) => {
ws.send(JSON.stringify({block: block}), () => {});
});
}
);
}
getAccountsWithTransactionCount(callback) {
let self = this;
self.getAccounts((err, addresses) => {
let accounts = [];
async.eachOf(addresses, (address, index, eachCb) => {
let account = {address, index};
async.waterfall([
function(callback) {
self.getTransactionCount(address, (err, count) => {
if (err) {
self.logger.error(err);
account.transactionCount = 0;
} else {
account.transactionCount = count;
}
callback(null, account);
});
},
function(account, callback) {
self.getBalance(address, (err, balance) => {
if (err) {
self.logger.error(err);
account.balance = 0;
} else {
account.balance = self.web3.utils.fromWei(balance);
}
callback(null, account);
});
}
], function(_err, account){
accounts.push(account);
eachCb();
});
}, function () {
callback(accounts);
});
});
}
getAccount(address, callback) {
let self = this;
async.waterfall([
function(next) {
self.getAccountsWithTransactionCount((accounts) => {
let account = accounts.find((a) => a.address === address);
if(!account) {
return next("No account found with this address");
}
next(null, account);
});
},
function(account, next) {
self.getBlockNumber((err, blockNumber) => {
if (err) {
self.logger.error(err);
next(err);
} else {
next(null, blockNumber, account);
}
});
},
function(blockNumber, account, next) {
self.getTransactions(blockNumber, blockNumber, (transactions) => {
account.transactions = transactions.filter((transaction) => transaction.from === address);
next(null, account);
});
}
], function (err, result) {
if (err) {
callback();
}
callback(result);
});
}
getTransactions(blockFrom, blockLimit, callback) {
this.getBlocks(blockFrom, blockLimit, true, (blocks) => {
let transactions = blocks.reduce((acc, block) => acc.concat(block.transactions), []);
callback(transactions);
});
}
getBlocks(from, limit, returnTransactionObjects, callback) {
let self = this;
let blocks = [];
async.waterfall([
function(next) {
if (!isNaN(from)) {
return next();
}
self.getBlockNumber((err, blockNumber) => {
if (err) {
self.logger.error(err);
from = 0;
} else {
from = blockNumber;
}
next();
});
},
function(next) {
async.times(limit, function(n, eachCb) {
self.web3.eth.getBlock(from - n, returnTransactionObjects, function(err, block) {
if (err){
self.logger.error(err);
return eachCb();
}
blocks.push(block);
eachCb();
});
}, next);
}
], function () {
callback(blocks);
});
}
subscribeToNewBlockHeaders() {
let self = this;
self.web3.eth.subscribe("newBlockHeaders", (err) => {
if (err) {
self.logger.error(err.message);
}
}).on("data", (block) => {
self.events.emit("blockchain:newBlockHeaders", block);
});
}
defaultAccount() {
return this.web3.eth.defaultAccount;
}
getBlockNumber(cb) {
return this.web3.eth.getBlockNumber(cb);
}
setDefaultAccount(account) {
this.web3.eth.defaultAccount = account;
}
getAccounts(cb) {
this.web3.eth.getAccounts(cb);
}
getTransactionCount(address, cb) {
this.web3.eth.getTransactionCount(address, cb);
}
getBalance(address, cb) {
this.web3.eth.getBalance(address, cb);
}
getCode(address, cb) {
this.web3.eth.getCode(address, cb);
}
getBlock(blockNumber, cb) {
this.web3.eth.getBlock(blockNumber, true, cb);
}
getTransaction(hash, cb) {
this.web3.eth.getTransaction(hash, cb);
}
getGasPrice(cb) {
const self = this;
this.onReady(() => {
self.web3.eth.getGasPrice(cb);
});
}
getNetworkId() {
return this.web3.eth.net.getId();
}
ContractObject(params) {
return new this.web3.eth.Contract(params.abi, params.address);
}
deployContractObject(contractObject, params) {
return contractObject.deploy({arguments: params.arguments, data: params.data});
}
estimateDeployContractGas(deployObject, cb) {
return deployObject.estimateGas().then((gasValue) => {
cb(null, gasValue);
}).catch(cb);
}
deployContractFromObject(deployContractObject, params, cb) {
const self = this;
let hash;
let calledBacked = false;
function callback(err, receipt) {
if (calledBacked) {
return;
}
if (!err && !receipt.contractAddress) {
return; // Not deployed yet. Need to wait
}
if (interval) {
clearInterval(interval);
}
calledBacked = true;
cb(err, receipt);
}
// This interval is there to compensate for the event that sometimes doesn't get triggered when using WebSocket
// FIXME The issue somehow only happens when the blockchain node is started in the same terminal
const interval = setInterval(() => {
if (!hash) {
return; // Wait until we receive the hash
}
self.web3.eth.getTransactionReceipt(hash, (err, receipt) => {
if (!err && !receipt) {
return; // Transaction is not yet complete
}
callback(err, receipt);
});
}, 500);
deployContractObject.send({
from: params.from, gas: params.gas, gasPrice: params.gasPrice
}, function (err, transactionHash) {
if (err) {
return callback(err);
}
hash = transactionHash;
}).on('receipt', function (receipt) {
if (receipt.contractAddress !== undefined) {
callback(null, receipt);
}
}).then(function (_contract) {
if (!hash) {
return; // Somehow we didn't get the receipt yet... Interval will catch it
}
self.web3.eth.getTransactionReceipt(hash, callback);
}).catch(callback);
}
determineDefaultAccount(cb) {
const self = this;
self.getAccounts(function (err, accounts) {
if (err) {
self.logger.error(err);
return cb(new Error(err));
}
let accountConfig = self.config.blockchainConfig.account;
let selectedAccount = accountConfig && accountConfig.address;
const defaultAccount = selectedAccount || accounts[0];
self.setDefaultAccount(defaultAccount);
cb(null, defaultAccount);
});
}
registerWeb3Object() {
// doesn't feel quite right, should be a cmd or plugin method
// can just be a command without a callback
this.events.emit("runcode:register", "web3", this.web3, false);
}
}
BlockchainConnector.ACCEPTED_TYPES = ['rpc', 'ws', 'vm'];
module.exports = BlockchainConnector;